George McAfee, a former running back for the Chicago Bears who developed dementia in his twilight years, died an excruciating and humiliating death in 2009 while in the care of an Atlanta assisted-living facility.

The pro-football Hall of Famer wandered unsupervised into a cleaning room and drank from a bottle of industrial-strength detergent. The caustic chemical burned his lips, esophagus and lungs before he died in the hospital, according to his family, which settled with the Emeritus Corporation, the company that ran the facility and took responsibility for his death.

When caregivers found McAfee, his lips were black and his face looked like a "horror show death mask," according to his daughter, Cheryl Morgan, 66, of Stone Mountain, Ga.

"It was horrible, horrible," she told ABCNews.com. "I cannot begin to tell you how horrific it was. We just hope he wasn't conscious."

Now, filmmaker A.C. Thompson of ProPublica, in collaboration with reporter Jonathan Jones and PBS' "Frontline," has taken a critical look at the for-profit world of assisted-living facilities. In addition to quasi-independent care, the facilities offer so-called "memory units" for families who want a safe and home-like environment for their loved ones who are suffering from dementia and Alzheimer's disease.

The facilities, sometimes with spiral staircases and lush grounds, are loosely regulated, depending on the state, and often don't have a full-time nurse on duty, according to the "Frontline" report, in contrast to nursing homes, which are federally funded and, therefore, under tougher scrutiny.

"I realized that, in some ways, this is a secret world and people don't understand what's going on and the rules governing it," Thompson told ABCNews.com.

Conditions are difficult and workers are paid minimum wage, according to Thompson, who interviewed staff workers and elder care advocates.

"There is a high burn-out factor and people often don't last," said Thompson. "You get a revolving cast of caregivers.

For a lot of people without dementia, these facilities are great," he said. "They don't necessarily need a nurse to tend to them around the clock and they don't need an institutional setting.

"We met lots of compassionate, considerate, smart caregivers," he added. "My concern is that it's a loosely regulated industry and things can go traumatically wrong. The industry has an incredible emphasis on sales and revenue -- and making as much money as possible."

Researching consumer lawsuits and complaints in numerous facilities nationwide that led to injuries and death, Thompson cited inadequate staffing ratios, limited training and policies that put profit over patients' well-being.

One staffer said in the film that training consists of one eight-hour session on how to feed and talk to dementia patients.

Thompson examined numerous public files on assaults between residents, sexual assaults by caregivers and patients who went missing. One, according to the documentary, was never found.

Thompson alleged these units are marketing tools and "money makers."

The documentary focuses on one of the industry's leaders, Seattle-based Emeritus Corporation, whose advertising slogan is, "Our family is committed to yours."

Emeritus is the largest company in the assisted living business. It is publicly traded, with $1.6 billion in revenues a year, and is responsible for 42,000 residents at 480 facilities around the country.

"I adamantly disagree that we put profits ahead of service care," Granger Cobb, president and CEO of Emeritus, told ABCNews.com.

"Senior living is a highly competitive industry," he said. "It's a very emotional time when a family considers many assisted living options and they reach out to friends and family and physicians and clergymen and ask for referrals.

Having a strong reputation is critical. Otherwise, we don't last very long. I don't think a company would ever sacrifice that reputation and customer satisfaction for some short-term gain on bottom line."

But McAfee's family sued Emeritus, which settled out of court. Facility records eventually revealed that for a half hour no one was on duty in the wing where McAfee found the cleaning fluid.

"George McAfee was an absolute tragic accident that was horrific and the community was devastated," he said. "We sincerely regret the pain and trauma they experienced. … There has never been a similar accident in 20 years since we were founded."

Thompson's year-long investigation also uncovered the case of a Texas woman who froze to death on Christmas day in 2004. Her family sued Emeritus and settled confidentially. He also found several cases of patients falling to their deaths at Emeritus facilities.

"When dealing with this many residents, particularly a population that can have unpredictable behavior or is frail or high-risk to begin with, we will have a situation with them from time to time," he said.

In the next 15 years, the number of Americans who are 70 and older will grow by 1 million annually, Cobb noted in the film.

"Memory units are an ideal choice for those who are memory impaired but who don't have intense medical needs," he said. "The environment feels more normal and home-like to them."

"Frontline" noted that because of their age, most residents in this age group are on multiple medications -- often 10 to 15 a day -- and said lack of medical services and understaffing can lead to mistakes.

The film cited one incident when only one employee was on staff at night.

But Emeritus' Cobb said that, "generally speaking," company facilities have at least three staff members on a night -- two caregivers and a med tech.

In the documentary, former Emeritus staff members and nurses at numerous facilities described a "back-door" policy, saying that they were encouraged not to let patients leave these units for nursing homes to keep beds full.

"Generally, families want to keep their loved ones with us as long as possible and defer moving to skilled nursing," said Cobb. "If a resident requires skilled nursing, we work with the family to arrange as quickly and smoothly as possible."

McAfee was at several other facilities before coming to Cypress Gardens near his daughter, Morgan, in Georgia in 2006. The fee was $4,000 a month -- "a lot of money," she said.

The family thought they had "struck gold" -- a far cry from the sterile corridors of a nursing home where they saw patients sit listless in wheelchairs.

But when Emeritus took over the facility shortly thereafter, "it went down from there," said Morgan, alleging his sheets were never changed, the room and he were rarely cleaned and he "looked like a dirty old man."

At first, her father had regular caregivers who knew his tendency to be obstinate and to wander. But soon, Emeritus began to rotate staff, according to Morgan.